Abstract: A surface-treated metal material wherein a film comprising an organic polymer compound having 5-100 mg of carbon per m.sup.2 and a phosphoric acid compound having 1-30 mg of phosphorus per m.sup.2 is formed on a metal surface, the ratio C/P of carbon atoms C to phosphorus atoms P in the film lying within the range 2-25.

Abstract: The present invention relates to a surface treating dispersion for treating a surface of zinc or of an alloy of zinc and aluminum, the surface treating dispersion comprising an aqueous solution having a pH of below 3 and a complex formed from at least one species of metal oxo ion in conjunction with at least one species of hetero ion, the metal oxo ion being selected from the group consisting of molybdate, tungstate and vanadate, the hetero ion being selected from the group consisting of phosphorus (V), aluminum (III), silicon (IV), manganese (II), manganese (IV), zirconium (IV), titanium (IV), tin (IV), cerium (III) and nickel (II); and with a film forming acid tolerant resin compatible with the selected ions.

Abstract: This invention relates to a process comprising the steps of contacting a metal surface with an aqueous composition comprising water and specific amounts by weight of phosphate ions, condensed phosphate ions and water soluble polymer molecules of a specific general formula, separating the contacted metal surface from the aqueous composition, rinsing with water and heating.

Abstract: An aluminum-alloy article such as a fastener is prepared by providing an aluminum-alloy article that is not in its final heat-treated state, and is preferably in its annealed state. A curable organic coating material is also provided. The method includes applying the organic coating material to the aluminum-alloy article, and heat-treating the coated aluminum article to its final heat-treated state, thereby simultaneously curing the organic coating.

Abstract: An aqueous liquid composition for treating the surface of copper-containing metals is a dispersion and/or solution in water and organic solvent, at least one silane coupling agent having a functional moiety selected from vinyl, mercapto, amino and glycidyloxy moieties bonded to one carbon atom in the silane coupling agent and other epoxy moieties bonded to two adjacent carbon atoms in the silane coupling agent and at least one copper inhibitor compound selected from azoles, azines, aromatic secondary amines, and aromatic diacylhydrazides. Treatment with this composition provides excellent migration resistance, an excellent solder resistance, and a very durable adhesiveness to a variety of copper containing metal surfaces.

Abstract: An aluminum-alloy article such as a fastener is prepared by providing an aluminum-alloy article precursor that is not in its final heat-treated state, and in one form is in its solution treated/annealed state. A curable organic coating material is also provided. The method includes anodizing the article precursor, preferably in chromic acid solution and without chemical sealing during anodizing, applying the organic coating material to the aluminum-alloy article precursor, and precipitation heat-treating the coated aluminum article precursor to its final heat-treated state, thereby simultaneously curing the organic coating. If the aluminum alloy temper is of the naturally aging type, it is optionally lightly deformed prior to precipitation treatment aging.

Abstract: A method and composition for treating metal surfaces to improve corrosion resistance and paint adhesion. The composition is a non-corrosive aqueous solution including water, a polymeric compound, an additive, and dispersed silica. In a preferred embodiment, the polymeric compound may be a polymer having a plurality of carboxylic functional groups and a plurality of hydroxyl groups. The polymeric compound may be a bifunctional copolymer or the reaction product of a first polymer having a plurality of carboxylic functional groups (e.g., polyacrylic acid or polymethylvinylmaleic anhydride), and a second polymer having a plurality of hydroxyl groups (e.g., polyvinyl alcohol). The additive is selected from at least one of: (i) an acid of a group IV-B element and a weak base, and (ii) an ammonium salt of a group IV-B compound such as ammonium zirconium carbonate. An exemplary acid of a group IV-B element is fluotitanic acid and an exemplary weak base is ammonium hydroxide.

Abstract: To prevent the deterioration in water-resistant secondary adherence that occurs during prolonged use of a fluoride-containing phosphate conversion coating liquid composition to form a conversion coating on metal surfaces that are at least partly aluminiferous, the aluminum compound-containing sludge produced in the phosphate conversion coating liquid composition as it is used is coagulated and sedimented by adding at least one cationic polymeric coagulant to the sludge-containing phosphate conversion coating liquid composition.

Abstract: Aluminum or aluminum alloy sheet is treated with an aqueous composition containing: (a) acrylic polymers or copolymers with a glass transition temperature of no greater than 0.degree. C., and (b) a water soluble zirconium compound, and dried. Preferably, the drying process is at an elevated temperature without intermediate rinsing. The coated aluminum/alloy surfaces exhibit corrosion resistance and paint adherence through a forming operation.

Abstract: A solution in water of fluorometallate and phosphate anions, divalent and/or trivalent metal cations, and polyhydroxylaminomethyl substituted polymers of vinyl phenol(s) provides an effective and economical post-rinse for conversion coatings, particularly predominantly zinc phosphate coatings that also contain manganese and may contain other cations.

Abstract: Described is a process using a no-rinse technique for the production of a chromium-free conversion layer on the surface of aluminum and its alloys by treating with an aqueous solution having a pH between 1 and 3.5 and containing titanium and/or zirconium plus an organic film-forming agent. The process is characterized in that the surface is brought into contact with a solution containing a) 2.2 to 22.0 g/l of Zr(IV) and/or 1.4 to 14.0 g/l of Ti(IV), b) 2.4 to 24.0 g/l of orthophosphate, c) 3.0 to 30.0 g/l of fluoride, d) 0.15 to 1.5 g/l of a water-soluble or homogeneously water-dispersible organic film former and, after a contact time between 1 and 40 seconds, the wet surface is allowed to dry, without rinsing, at a temperature between 50.degree. and 125.degree. C. Also described are aqueous concentrates for use in the process.

Abstract: A method and composition for coating a metal for use in connection with improving corrosion resistance and paint adhesion. The composition is a non-corrosive ester cross-linked polymer system having a plurality of carboxylic functional groups and a plurality of hydroxyl groups. The polymer system may be a bifunctional copolymer or the reaction product of a first polymer having a plurality of carboxylic functional groups (e.g. polyacrylic acid or polymethylvinylmaleic anhydride), and a second polymer having a plurality of hydroxyl groups (e.g. polyvinyl alcohol). The resulting reaction product of these two polymers is a cross-linked polymeric blend. A compound of a Group IV-B element may be added to this polymer blend to increase the degree of cross-linking and improve paint adhesion and corrosion resistance. Such a Group IV-B compound may be an acid such as fluozirconic acid, fluotitanic acid or fluohafnic acid, or a salt such as ammonium zirconium carbonate.

Abstract: A method and composition for coating a metal for use in connection with improving corrosion resistance and paint adhesion. The composition is a non-corrosive ester cross-linked polymer system having a plurality of carboxylic functional groups and a plurality of hydroxyl groups. The polymer system may be a bifunctional copolymer or the reaction product of a first polymer having a plurality of carboxylic functional groups (e.g. polyacrylic acid or polymethylvinylmaleic anhydride), and a second polymer having a plurality of hydroxyl groups (e.g. polyvinyl alcohol). The resulting reaction product of these two polymers is a cross-linked polymeric blend. A compound of a Group IV-B element may be added to this polymer blend to increase the degree of cross-linking and improve paint adhesion and corrosion resistance. Such a Group IV-B compound may be an acid such as fluozirconic acid, fluotitanic acid or fluchafnic acid, or a salt such as ammonium zirconium carbonate.

Abstract: A highly corrosion-resistant, paint-adherent, and lubricating polymer-containing coating on a metal surface can be formed by contact with an aqueous solution (pH=2.0 to 6.5) that contains an acidic compound and polymer with the following formula (I): ##STR1## in which the X bonded to the phenyl ring in formula (I) represents a hydrogen atom, a hydroxyl group, a C.sub.1 to C.sub.5 alkyl group, a C.sub.1 to C.sub.5 hydroxyalkyl group, a C.sub.6 to C.sub.12 aryl group, a benzil group, a benzal group, an unsaturated hydrocarbon moiety condensed to the phenyl ring so as to form a naphthalene ring, or a group corresponding to formula (II): ##STR2## in which R.sup.1 and R.sup.2 in formula (II) each independently represent a hydrogen atom, a hydroxyl group, a C.sub.1 to C.sub.10 alkyl group, or a C.sub.1 to C.sub.10 hydroxyalkyl group; the Y.sup.1 and Y.sup.

Abstract: A surface of aluminiferous metal is brought into contact at 30.degree. C. to 65.degree. C. for 5 to 60 seconds with a surface treatment bath with a pH of 2.0 to 6.5 that contains phosphate ion, condensed phosphate ion, and a water soluble polymer in the following weight proportions: 1-30: 0.1-10: 0.2-20. This is followed by a water rinse and drying by heating. The water soluble polymer has a chemical structure conforming with formula (I): ##STR1## in which (i) each of X.sup.1 and X.sup.2 represents a hydrogen atom, a C.sub.1 to C.sub.5 alkyl group, or a C.sub.1 to C.sub.5 hydroxyalkyl group; (ii) each of Y.sup.1 and Y.sup.2 represents a hydrogen atom or a moiety "Z" that conforms to formula (II) or (III): ##STR2## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 represents a C.sub.1 to C.sub.10 alkyl group or a C.sub.1 to C.sub.10 hydroxyalkyl group; (iii) the average value for the number of Z moieties substituted on each phenyl ring in the polymer molecule is from 0.2 to 1.

Abstract: A method for treating a metal surface involves contacting the metal surface with an aqueous silicate solution, contacting the silicate-coated metal surface with an aqueous organo-functional silane solution, and then contacting the silane-coated metal surface with a chrome-free pretreatment. Preferably, the bath containing the aqueous silicate solution also includes a cleaning agent for cleaning the metal surface. Alternatively, the metal surface may be cleaned in a separate step before the metal surface is contacted with the aqueous silicate solution and, optionally, the metal surface is rinsed with water after the metal surface is cleaned and before the metal surface is contacted with the aqueous silicate solution. The silicate-coated metal surface may be rinsed with water before it is contacted with an aqueous organo-functional silane solution. In addition, the silane-coated metal surface may be rinsed with water before it is contacted with a chrome-free pretreatment.

Abstract: Zinciferous and/or aluminiferous metal surfaces can be passivated by treatment with a chromium-free aqueous solution of phosphoric acid and molybdenum that is at least partially in a valence state lower than +6, to produce, especially with an acrylic overcoating, a surface as resistant to corrosion as the surface of the same substrate after passivation with conventional liquid compositions that contain hexavalent chromium.

Abstract: A process for measuring the coating weight of a dried-in-place non-chromate polyacrylamide based conversion coating is disclosed. An ammonium hexafluorotitanate tracer added to such a conversion coating was found to not adversely affect coating properties. The tracer was found to remain proportional to the polymer matrix when the coating was analyzed by X-ray fluorescence.

Abstract: A method of forming a protective coating on aluminum and aluminum alloy surfaces to improve adherence of siccative coatings such as inks, paints, and lacquers. The method involves rinsing acid treatments from aluminum surfaces followed by coating the aluminum surfaces with a polymeric composition. The method provides improved adhesion of siccative coverings to treated aluminum surfaces over chrome containing and non-chrome containing fluoroacid and polymer mixture treatments.

Abstract: A strip of highly reflective aluminum protected by a conversion coating and a light-permeable fluoropolymer coating which is non-adhesively interstitially mechanically bonded to the microscopic irregularities of the conversion coated surface. The highly reflective strip may be substituted for polished stainless steel and/or bi-metal and used under aggressive conditions for a prolonged period without deleteriously affecting the initial D/I (distinctness of reflected image) of the shaped strip. The strip of arbitrary length may be shaped in rolling dies so that at least a portion of the strip has a radius of less than 10 mm without damaging or separating the fluoropolymer coating. The specific steps of the claimed process require starting with a bright-rolled clean strip which is conversion coated to carry a thin metal compound coating. The reflective conversion coated surface is coated with the fluoropolymer while maintaining at least 80% D/I.

Abstract: A coating preparation for pretreating metals comprises an acrylic acid or a derivative thereof and barium hydroxide in a proportion by weight of 1:0.08-0.30, as well as chromium compounds, the remainder being conventional additives and water. The amount of acrylic acid or derivative thereof is preferably 2-6% by weight. The amount of chromic acid in the chromium compounds in the coating preparation depends on the type of the metal substrate to be treated. Such a preparation combines, in a single preparation, the desired properties for conversion of the metal and adhesion, which means that instead of 2 separate layers, 1 layer is sufficient.

Abstract: Aluminum surfaces are protected with increased corrosion resistance by anodize, and sealing with a liquid fatty acid free of flammable solvents, suitably in the presence of a heterocyclic aromatic azole treating agent where the aluminum surface is of a copper containing aluminum alloy.

Abstract: A hydrophilic surface-treating aqueous solution and a hydrophilic surface-treating method are provided to form a film which can maintain its hydrophilicity. The hydrophilic surface-treating aqueous solution contains as main components polyglutamic acid, basic compound, and aqueous resin if necessary. This surface-treating solution and method enable the forming of a film on the surface of aluminum series metals which are used for aluminum fins of heat exchangers, and confer the film's anticorrosion properties, superior hydrophilicity and high hydrophilic permanency, while remarkably suppressing an offensive odor.

Abstract: Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate .alpha.-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal.

Abstract: A bath for treating metal surfaces for the formation thereon of composite films for the cold working of metal advantageously comprises an otherwise conventional conversion coating bath that also contains organic cationic polymer having at least 1 cationic nitrogen atom per molecule and having a molecular weight of 1,000 to 1,000,000, or a salt of such a polymer. Major improvements in the lubrication properties, particularly in the seizure resistance, can be achieved by applying out a conventional lubrication treatment on such a composite film. Specifically, practical operating limits in metal cold working, e.g., the working degree or ratio, working speed, tool life, and the like, can be increased in a single step. This is useful in terms of improving productivity, product stability, cost reduction, and the like.

Abstract: An apparatus and method is provided for automated periodic removal of metal ions and contaminants from a chemical bath comprising a latex solution containing charged latex particles and having an acidic pH, used for forming a coating by autodeposition. The system includes a tank containing a chemical bath, an ion exchange column for removing the metal ion contaminants, circulating pump, metal composition sensors, and equipment for regeneration of the ion exchange column. The system particularly includes a filter located at the inlet to the ion exchange column for removing solid particulates, including coagulated latex and debris from the coating solution, while permitting the uncoagulated latex particles to pass through to the ion exchange column.

Abstract: Heating an aqueous mixture of a fluoroacid such as H.sub.2 TiF.sub.6 and an oxide, hydroxide, and/or carbonate such as silica produces a clear mixture with long term stability against settling of any solid phase, even when the oxide, hydroxide, or carbonate phase before heating was a dispersed solid with sufficiently large particles to scatter light and make the mixture before heating cloudy. The clear mixture produced by heating can either be mixed with water soluble and/or water dispersible polymers, for example with dispersed polymers of the diglycidyl ether of bisphenol-A or an acrylic acid polymer, or with soluble hexavalent and/or trivalent chromium, to produce a composition that improves the corrosion resistance of metals treated with the composition, especially after subsequent painting.

Abstract: A heavy metal and fluoride free pretreatment for a metal surface which enhances corrosion resistance and surface adhesion properties is described. The pretreatment is an aqueous solution of an anionic polyacrylamide which can be rinsed or dried in place.

Abstract: A method of providing color to a polyacrylamide based, dried-in-place, non-chromate conversion coating is provided. The addition of a phthalo green pigment and optionally a nonionic surfactant to an aqueous, dried-in-place conversion coating treatment solution provides for a colored conversion coating without adversely affecting the corrosion resistance or adhesion properties of the conversion coating.

Abstract: Cleaned or chemically pretreated metal surfaces are modified using aqueous solutions of amino-containing organic polymers, the metal surfaces thus modified being particularly suitable for coating by cathodic electrodeposition.

Abstract: A novel process for bonding a fluoropolymer to a metal surface, the process including flowing the fluoropolymer on the metal surface at a temperature at or above the transition temperature of the fluoropolymer and then holding the fluoropolymer at a temperature incrementally above the melting temperature of the fluoropolymer. The holding period allows the chlorine or fluorine in the chloro-fluoro-polymer subunits of the fluoropolymer to react with the metal and thereby securely bond the fluoropolymer to the metal surface.

Abstract: A bake hardenable steel sheet ready for deep drawing is coated on at least one side with a continuous chromium bearing epoxy coating. The sheet is roll coated with continuous liquid film containing at least 2 wt. % of a water dispersible or emulsifiable epoxy resin or a mixture of resins containing the epoxy resin, at least 0.5 wt. % of a chromium compound and 25-97 wt. % of water. The liquid coated sheet is induction heated at a temperature of 149-227.degree. C. for sufficient time to form a coating resistant to dissolution of chromium and a steel base metal having a yield point elongation no greater than 0.3% and retaining good bake hardenability characteristics. The chromium bearing epoxy coating is impervious to moisture, can readily be welded and possesses sufficient toughness and lubricity to allow deformation of the sheet without additional external lubricant. A deeply drawn article formed from the sheet has enhanced painting characteristics.

Abstract: A method for inhibiting corrosion of a metal surface in a liquid medium is described. The method comprises incorporating into the medium a corrosion inhibiting amount of a combination of a surfactant that forms a bilayer on the metal surface in the fluid and a corrosion inhibitor that solubilizes in the medium in the presence of the surfactant. The amount of surfactant is sufficient to produce a bilayer on the metal surface in the medium. The combination isa. an anionic surfactant that forms a bilayer on the metal surface and a cationic corrosion inhibitor;b. a cationic surfactant that forms a bilayer on the metal surface and an anionic corrosion inhibitor;c. an ionic surfactant that forms a bilayer on the metal surface and an ionic corrosion inhibitor having a pendent, generally straight chain hydrocarbon or substituted hydrocarbon moiety of from about 10 to about 18 carbon atoms; ord. an ionic surfactant that forms a bilayer on the metal surface and a non-ionic corrosion inhibitor.

Abstract: A non-chromate conversion coating for metal surfaces such as aluminum, steel, galvanized steel and zinc-aluminum steel consisting of an aqueous solution of a cationic polymer, an alkaline aqueous silicate and an organofunctional silane.

Abstract: A process for measuring the coating weight of a dried-in-place non-chromate polyacrylamide/surfactant based conversion coating is disclosed. An ammonium hexafluorotitanate tracer added to such a conversion coating was found to not adversely affect coating properties. The tracer was found to remain proportional to the polymer matrix when the coating was analyzed by X-ray fluorescence.

Abstract: A chromium free conversion coating at least equivalent in corrosion protective quality to conventional chromate conversion coatings can be formed on metals, particularly cold rolled steel, by a dry-in-place aqueous acidic liquid comprising:(A) a component of anions, each of said anions consisting of (i) at least four fluorine atoms and (ii) at least one atom of an element selected from the group consisting of titanium, zirconium, hafnium, silicon, and boron, and, optionally, (iii) ionizable hydrogen atoms, and, optionally, (iv) one or more oxygen atoms;(B) a component of cations of elements selected from the group consisting of cobalt, magnesium, manganese, zinc, nickel, tin, zirconium, iron, and copper; the ratio of the total number of cations of this component to the total number of anions of component (A) being at least 1:5;(C) sufficient free acid to give the composition a pH in the range from 0.5 to 5.

Abstract: A chromium free conversion coating at least equivalent in corrosion protective quality to conventional chromate conversion coatings can be formed on metals, particularly galvanized steel, by a dry-in-place aqueous acidic liquid comprising:(A) a component of anions, each of said anions consisting of (i) at least four fluorine atoms and (ii) at least one atom of an element selected from the group consisting of titanium, zirconium, hafnium, silicon, and boron and, optionally, (iii) one or more oxygen atoms;(B) a component of cations of elements selected from the group consisting of cobalt, magnesium, manganese, zinc, nickel, tin, zirconium, iron, aluminum and copper; the ratio of the total number of cations of this component to the total number of anions of component (A) being at least 2:5; and(C) sufficient free acid to give the composition, after dilution with from 1 to 19 times its own weight of water, a pH in the range from 0.5 to 5.

Abstract: A chromium free conversion coating at least equivalent in corrosion protective quality to conventional chromate conversion coatings can be formed on metals, particularly cold rolled steel, by a dry-in-place aqueous acidic liquid comprising:(A) a component of anions, each of said anions consisting of (i) at least four fluorine atoms and (ii) at least one atom of an element selected from the group consisting of titanium, zirconium, hafnium, silicon, and boron, and, optionally, (iii) ionizable hydrogen atoms, and, optionally, (iv) one or more oxygen atoms;(B) a component of cations of elements selected from the group consisting of cobalt, magnesium, manganese, zinc, nickel, tin, zirconium, iron, and copper; the ratio of the total number of cations of this component to the total number of anions of component (A) being at least 1:5;(C) sufficient free acid to give the composition a pH in the range from 0.5 to 5.

Abstract: A process for measuring the coating weight of a dried-in-place non-chromate polyacrylamide/surfactant based conversion coating is disclosed. An ammonium hexafluorotitanate tracer added to such a conversion coating was found to not adversely affect coating properties. The tracer was found to remain proportional to the polymer matrix when the coating was analyzed by X-ray fluorescence.

Abstract: A chromating treatment composition particularly suitable for preparing aluminum and stainless steel for clear coating comprises water, anions containing hexavalent chromium, trivalent chromium cations, phosphate ions, dry process finely divided silica, and acrylic and/or methacrylic acid polymer or copolymer in such amounts that:(A) the concentration of the total of hexavalent and trivalent chromium atoms is in the range from 1 to 60 g/L;(B) the (trivalent chromium atom)/(hexavalent chromium atom) weight ratio is in the range from 0.6 to 2.5;(C) the (phosphate ion)/(total chromium atoms in hexavalent chromium ions and trivalent chromium ions) weight ratio is in the range from 0.5 to 4.5;(D) the (dry process silica)/(total chromium atoms in hexavalent chromium ions and trivalent chromium ions) weight ratio is in the range from 0.1 to 5.

Abstract: Methods of forming a dried in place conversion coating on metal surfaces such as aluminum and aluminum alloys. The methods comprise contacting the metal with an aqueous solution of a water soluble maleic or acrylic acid/allyl ether copolymer alone or with an acid.

Abstract: A non-chromate conversion coating for metal surfaces such as aluminum, steel, galvanized steel and zinc-aluminum steel consisting of an aqueous solution of a cationic polymer, an alkaline aqueous silicate and an organofunctional silane.

Abstract: A coating composition for metallic surfaces contains:(1) Cr.sup.6+, or Cr.sup.6+ and Cr.sup.3+,(2) 1-50% of lubricant(s) dispersed by a nonionic emulsifying agent,(3) acryl-series polymer emulsion, which is obtained by emulsion-polymerizing, by means of a nonionic emulsifying agent which is essentially free of anionic and cationic emulsifying agent and which contains a polyoxyethylene-polyoxypropylene block polymer, monomers of A), B), and C):A) a monomer of ethylene-series, unsaturated carboxylic acidB) one or more monomers selected from a), b), and c):a) alkoxyethylene(metha)acrylamide and its derivative(s) expressed by the following general formula ##STR1## X is CnH.sub.2n+1 (n=0 or 1) Y is CmH.sub.2m+1 (m=0-4)b) acid phospho-oxyalkyl(metha)acrylate, andc) alkoxy-alkyl(metha)acrylateC) one or more acryl-series monomers (a part of which may consist of 2)(c)).

Abstract: A method of cleaning a metal surface includes covering the portion of the metal surface with a cleaning tape. The cleaning tape is chromium in combination with a fluoride ion source bound together by fibrillated polytetrafluoroethylene. This is applied to the portion of the area to be cleaned and is subject to heat treatment at about 1800.degree. F. and a reducing atmosphere of preferably hydrogen. This effectively cleans only the area covered by the tape. Further, the tape and binder format acts to force fluoride ions into the cracks on the surface providing a significantly improved cleaning operation.

Abstract: A superior protective prepainting treatment for tin plated steel surfaces, particularly DI cans, may be achieved by contacting the surface with an aqueous liquid composition containing from 1 to 30 g/L of phosphate ions, from 0.1 to 5 g/L of condensed phosphate ions, from 0.5 to 5 g/L of reducing agent, and from 0.1 to 20 g/L of dissolved solids of a water soluble aminated poly{vinyl phenol} resin.

Abstract: Heating an aqueous mixture of a fluoroacid such as H.sub.2 TiF.sub.6 and an oxide, hydroxide, and/or carbonate such as silica produces a clear mixture with long term stability against settling of any solid phase, even when the oxide, hydroxide, or carbonate phase before heating was a dispersed solid with sufficiently large particles to scatter light and make the mixture before heating cloudy. The clear mixture produced by heating can either be mixed with water soluble and/or water dispersible polymers, for example with dispersed polymers of the diglycidyl ether of bisphenol-A or an acrylic acid polymer, or with soluble hexavalent and/or trivalent chromium, to produce a composition that improves the corrosion resistance of metals treated with the composition, especially after subsequent painting.

Abstract: Substantially improved retention of hydrophilicity after exposure to high temperature can be provided on a metal substrate, particularly an aluminum alloy of the type used for heat exchanger fins by an aqueous liquid hydrophilicizing treatment composition containing acrylic and/or methacrylic acid polymer or copolymer, polyether alcohol, and alkali metal silicate. The treatment composition may also contain an anti-microbial agent and additional alkalinizer. The hydrophilicizing treatment is preferably applied over a conventional conversion coating, particularly a chromium phosphate or chromium oxide conversion coating.

Abstract: Precision ferrous metal parts subject to severe friction and corrosion in e are nitrided, preferably in a bath of molten salts based on CNO.sup.- cyanate ions, oxidized, preferably in baths of molten oxidizing alkaline salts, and then impregnated with a hydrophobic wax. A layer after the nitriding and oxidation steps is formed of a close-packed deep sub-layer and a porous superficial sub-layer ranging in thickness between 5 and 25 .mu.m, and exhibiting through pores ranging between 0.2 and 3 .mu.m in diameter. The impregnation wax is an organic compound with a high molecular weight between 500 and 10,000, with a surface tension in the liquid state ranging between 10 and 73 mN/m, the contact angle between the solid phase of the superficial layer and the wax in the liquid state ranging between 0 and 75.degree. C.

Abstract: An aqueous coating solution for zinc containing metals such as galvanized iron and steel. The coating solution is resistent to the formation of zinc induced sludge and can be operated with little or no overflow. The aqueous treatment solution contains from 0.1 to 10 grams per liter of a fluorometallic acid, from 0.015 to 6 grams per liter of a salt of a transition metal, from 1 to 30 grams per liter zinc; and optionally from 0.1 to 3 grams per liter a polymer of acrylic acid, methacrylic acid, or an ester thereof with a C1 to C8 alkanol.

Abstract: A non-chromate pretreatment for aluminum and zinc-aluminum galvanized steel is disclosed which comprises a polyacrylic acid or homopolymers and copolymers thereof, a molybdate, and a dihydrohexafluo acid.